In general, a fuel cell vehicle in which a fuel cell system is mounted generates electricity by supplying hydrogen used as fuel to a fuel cell stack and is driven by operating an electric motor with the electricity that is generated by the fuel cell stack.
Here, the fuel cell system is a kind of generation system that directly electrochemically converts chemical energy of fuel to electrical energy within a fuel cell stack instead of changing to a heat by combustion.
In such a fuel cell system, hydrogen having high purity is supplied from a hydrogen storage tank to an anode of a fuel cell, and air of the atmosphere is directly supplied to a cathode of the fuel cell using an air supply apparatus such as an air blower.
Accordingly, the hydrogen that is supplied to the fuel cell stack is separated into protons and electrons at a catalyst of the anode, and the separated protons are moved to the cathode through a polymer electrolyte membrane, and oxygen that is supplied to the cathode is coupled to electrons that are moved to the cathode through an external leading wire, and thus while water is generated, electrical energy is generated.
At the anode of the fuel cell, there exist unreacted hydrogen and moisture that moves from the cathode exhaust condensed water. The unreacted hydrogen is supplied to the fuel cell stack through a hydrogen recirculation device, and the condensed water is stored at a watertrap and is exhausted to the outside.
When the unreacted hydrogen is recirculated, in order to remove a foreign substance that is generated at the anode of the fuel cell stack, the fuel cell system purges hydrogen.
In the fuel cell system, when a gas or a coolant is not normally distributed, a performance of a specific cell is deteriorated and thus the specific cell may be degraded, and in order to prevent this, a current limitation function is applied.
Further, when the performance of a specific cell is deteriorated, a foreign substance such as hydrogen and moisture is purged through a purge valve, and by increasing a rotation speed of a hydrogen blower and an air blower, the performance of the cell may be recovered.
However, operation that increases a rotation speed of the blower and that exhausts the foreign substance, increases consumption of entire electrical energy and increases entire fuel consumption of a vehicle.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept and therefore it may contain information that does not form the prior art.